When is it too obsolete?

A Telegraph Report tells of a major UK hospital falling victim to a ransomware attack.

A source at the trust told Health Service Journal that the attack had affected thousands of files on the trust’s Windows XP operating system, and the trust’s file sharing system between departments has been turned off while an investigation takes place.

Of course, what stands out there is the mention of Windows XP: this operating system was declared obsolete nearly three years ago – though some customers have been able to purchase extended support from Microsoft.  Was the hospital one of them?  Let’s assume not, for a moment – after all, the fee for that support is unlikely to be small.

On one level, that sounds like a classic case of cutting corners and reaping a bad outcome as a result: the longer software has been in circulation, the more likely it is to fall victim to someone probing it for vulnerabilities.  Software that’s no longer maintained will not be patched when such vulnerabilities are found, and as a result, anyone running it is easy prey.   Without a good backup strategy, ransomware can prove very expensive – and, at that, you need a backup strategy which takes account of the behaviour of ransomware, lest you find that the backup itself is as useless as the main data.

I don’t know the cost of extended support from Microsoft, but I’d be surprised if it was cheaper than the cost of licences for an up-to-date copy of the operating system: the reason for not upgrading is usually tied up in all the dependencies.  Old software needs old operating systems in order to run reliably. If your system isn’t broken, it’s easier to leave everything exactly as it was.  The world is full of old software.  It doesn’t naturally wear out, and so it may continue to be used indefinitely.  Until, that is, someone forcibly breaks it from outside.  Then you’ve suddenly got a big problem: you may pay the ransom, and get your data back.  But how long before you fall victim to another attack, because you’ve still got an obsolete system?

It’s easy to criticise people and organisations who fall victim to attacks on their out-of-date software: keeping everything updated is, you may say, part of the cost of doing business today.  But that’s easy to say, and less easy to do.  In the management of most other parts of the estate, you can do updates and maintenance at times to suit you and your cash-flow.  In the case of software maintenance, that decision may be taken out of your hands.  You might be forced into buying lots of new software – and then, suddenly, other software, and maybe even bespoke systems, as well as lots of new hardware, with costs suddenly spiraling out of control.

This problem is almost as old as the personal computer (if not older): but recent events make it much worse. First, the scale and impact of cyber attacks is raising the stakes quite alarmingly.  But meanwhile, computer technology has rather stabilized: a desktop PC doesn’t need to do anything markedly different now than it did ten years ago.  So whereas PCs used to get replaced every three years (with hard-up organisations stretching that to five, say), now there’s really no need to buy a new machine until five or six years have elapsed.  If you stretch that a bit, you will easily run past the end of the device’s support lifetime.  And then, you potentially reach a point of great instability.

And – above all – the real problem is that this is getting worse by the day.  Not only are PCs living longer, but we are adding random poorly-supported devices to the internet daily, in the name of tablets, e-readers, TVs, internet-of-things, and a dozen other causes.  Few of those are anywhere near as well-supported as Windows, and many will be expected to operate for a decade or more. It’s not going to be pretty.

Where is all the nodejs malware?

We’re using nodejs extensively in our current research project – webinos – and I have personally enjoyed programming with it and the myriad of useful 3rd-party modules available online.

However, I’ve always been concerned about the ease at which new modules are made available and may be integrated into bigger systems.  If I want to create a website that supports QR code generation, for example, as a developer I might do the following:

  1. Visit google and search for “nodejs qrcode”.  The first result that comes up is this module – https://github.com/soldair/node-qrcode .  From a brief look at the github page, it seems to do exactly what I want.
  2. Download the module locally using ‘npm install qrcode’.  This fetches the module from the npmjs registry and then installs it using the process defined in the package.json file bundled with this module.
  3. Test the module to see how it works, probably using the test cases included in the module download.
  4. Integrate the module into webinos and then add it to webinos’ package.json file.
  5. When the changes make their way into the main project, everyone who downloads and installs webinos will also download and install the qrcode module.

I’m going to go out on a limb and suggest that this is a common way of behaving.  So what risk am I (and anyone developing with nodejs modules) taking?

If you’re using nodejs in production, you’re putting it on a web server.  By necessity, you are also also giving it access to your domain certificates and private keys.  You may also be running nodejs as root (even though this is a bad idea).  As such, that nodejs module (which has full access to your operating system) can steal those keys, access your user database, install further malware and take complete control of your webserver.  It can also take control of the PCs you and your fellow developers use every day.

The targets are juicy and the protection is minimal.

And yet, so far, I have encountered no malware (or at least none that I know about).  Some modules have been reported, apparently, but not many.   Why is that?

It could partly be because the npmjs repository offers a way for malware to be reported and efficiently removed.  Except that it doesn’t.  It may do so informally, but it’s not obvious how one might report malware, and there’s no automatic revocation mechanism or update system for already-deployed modules.

It could be that the source code for most modules is open and therefore malware authors dare not submit malicious modules for fear of being exposed, and those that do rapidly are.  Indeed, in the case of the qrcode module (and most nodejs modules) I can inspect the source code to my heart’s content.  However, the “many eyes” theory of open source security is known to be unreliable and it is unreasonable to suppose that this would provide any level of protection for anything but the most simple of modules.

I can only assume, therefore, that there is little known nodejs malware because the nodejs community are all well-intentioned people.  It may also be because developers who use nodejs modules form a relationship with the developer of the module and therefore establish enough trust to rely on their software.

However, another way of putting it is: nobody has written any yet.

The problem isn’t unique – any third party software could be malicious, not just nodejs modules – but the growing popularity of nodejs makes it a particularly interesting case.  The ease at which modules can be downloaded and used, in combination with their intended target being highly privileged, is cause for concern.

Disagree?  Think that I’ve missed something?  Send me an email – details here.

Update – I’ve blogged again about this subject over at webinos.org

A new(ish) attack vector?

I just acquired a nice new Android-TV-on-a-stick toy.  £30 makes it an interesting amusement, whether or not it becomes part of daily use.  But that price-point also raises a whole lot of new potential for danger.

Like all Android devices, in order to do anything very interesting with it, I have to supply some Google account credentials when setting it up.  And then to play music from the Amazon Cloud, I have to give some Amazon credentials.  And then, likewise, for Facebook, or Skype, or whatever apps you might want to run on the thing.  When cheap devices abound, we are going to have dozens of them in our lives, just for convenience, and need to share accounts and content between them.

But there’s the rub: anyone could build and ship an Android device.  And beside having all the good behaviours baked in, it could also arrange to do bad things with any of those accounts. This is the trusted device problem thrown into sharp relief.  The corporate world has been wrestling with a similar issue under the banner of ‘bring your own device’ for some time now: but plainly it is a consumer problem too.  Whereas I may trust network operators to sell only phones that they can vouch for, the plethora of system-on-a-stick devices which we are surely about to see will occupy a much less well-managed part of the market.

could use special blank accounts on untrusted devices, but the whole point of having cloud-based services (for want of a better name) is that I can access them from anywhere.  A fresh Google account for the new device would work just fine – but it wouldn’t give me access to all the content, email, and everything else tied to my account.  In fact, the Google account is among the safer things on the new device: thanks to their two-step authentication, stealing the Google password is not enough to provide the keys to the kingdom (though, the authenticator runs on … an Android phone!).

The problem isn’t entirely new, nor purely theoretical: just recently there were news reports of a PC vendor shipping a tainted version of Windows on brand new desktops – and such complexities have concerned the owners of high-value systems for some time.  Management of the supply chain is a big deal when you have real secrets or high-integrity applications.  But in consumer-land, it is quite difficult to explain that you shouldn’t blindly type that all-important password wherever you see a familiar logo: it is fairly difficult to explain that there is scope for something akin to phishing via an attack on a subsystem you cannot even see

Would trusted computing technologies provide a solution?  Well, I suppose they might help: that initial step of registering the new device and the user’s account with the Google servers could contain a remote attestation step, wherein it ‘proves’ that it really is running a good copy of Android.  This might be coupled with some kind of secure boot mandated by a future OS version: you might couple that with trusted virtualization in order to offer safe compartments for valuable applications.

But these things are really quite fraught with complexity (in terms of technology, innovation, liability, network effects, and more) so that I fear their value would be in doubt.  Nevertheless, I don’t really see an alternative on the table at the moment.

You could invent a ‘genuine product’ seal of some kind – a hologram stuck to the product box, perhaps – but who will run that programme, and how much liability will they assume?  You could assume that more locked-down devices are safer – but, reconsidering the supply chain management problem again, how long before we see devices that have been ‘jailbroken’, tained, and re-locked, before being presented through legitimate vendors?

The model is quite badly broken, and a new one is needed. I’d like to hope that the webinos notion of a personal zone (revokable trust among a private cloud of devices) will help: now that the design has matured, the threat model needs revisiting.  The area’s ripe for some more research.

lock-down or personal control?

A little piece of news (h/t Jonathan Zittrain) caught my eye:

The gist is that Cisco have been upgrading the firmware in Linksys routers so that they can be managed remotely (under the user’s control, normally) from Cisco’s cloud.  The impact of this is hotly debated, and I think Cisco disputes the conclusions reached by the journalists at Extreme Tech.  Certainly there’s a diffusion of control, a likelihood of future automatic updates, and various content restrictions (against, for example, using the service – whatever that entails – for “obscene, pornographic, or offensive purposes”, things which are generally lawful), and a general diminution of privacy.

Some commentators have reacted by suggesting buying different products (fair enough, depending on where the market leads), ‘downgrading’ to older firmware (not a long-term solution, given the onward march of vulnerability discovery),  or flashing one’s own firmware from some open source router development project (this is a surprisingly fertile area).  To someone interested in trusted computing and secure boot, the latter is quite interesting – you can do it now, but can/should you be able to in the future?

One of the central themes of some of the stuff around secure boot is that we want cryptographically-strong ways to choose which software is and is not booted, and leave this choice well away from the users, because they can’t be trusted to make the right decision.  That’s not some patronizing comment about the uneducated or unaware – I’d apply it to myself.  (I speak as someone who hasn’t knowingly encountered a Windows virus/trojan/work in decades despite using Windows daily: I think my online behaviour is fairly safe, but I am under no illusions about how easy it would be to become a victim.)  Whilst there are good reasons to want to retain a general power to program something like a PC to do whatsoever I wish, I can imagine that the majority of internet-connected devices in the future will be really quite tightly locked-down.  And this, in general, seems a good thing. I don’t demand to be able to re-program my washing machine, and I shouldn’t be able to demand to re-program my digital photo frame, or even my TV set-top box.

However, whereas my washing machine has no immediate prospect of connection to the internet (though the smart grid could change all that), many other devices are connected – and their mis-design will compromise my privacy or my data’s integrity, or worse.  And, indeed, involuntary remote updates could break them or reduce their functionality (a mess that already exists, and is really not well-addressed by consumer protection legislation).  I might have a reasonably secure household of internet junk until some over-eager product manager decides to improve one of my devices overnight one day. I could wake to find that my household had seized up and all my privacy gone, if the attacker followed the locus of the product updates.  This really isn’t particularly far-fetched.

So, I am faced with a tension.  A paradox, almost.  I am not well-placed to make security decisions by myself; none of us is, especially when we don’t even realise the decisions we are making are security-related.  But in this complex advertising-driven world, those to whom I am likely to delegate (perhaps involuntarily) such decisions are (a) themselves imperfect, and much more worryingly (b) highly motivated to monetize my relationship with them in every way possible.  Goodbye privacy.

The market might help to remedy the worst excesses in these relationships,  but when its dominated by large vendors suing each other over imagined patent infringements, I’m not optimistic about it resolving this tension in a timely manner.

Regulation could be a solution, but is seldom timely and often regulates the wrong thing (as the current mess of cookie regulation in the EU amply demonstrates).

Perhaps there is a role for third-party, not-for-profit agencies which help to regulate the deployment of security and privacy-related technologies – receiving delegated control of a variety of authorization decisions, for example, to save you from wondering if you want App X to be allowed to do Y.  They could in principle represent consumer power and hold the ring against both the vendors who want to make the user into the product and the attackers whose motives are simpler.  But will we build technologies in such a way as to permit the rise of such agencies?  It will take a concerted effort, I think.

Any other ideas?

Centre of Excellence

Today, the University is recognised by GCHQ as an Academic Centre of Excellence in Cyber Security Research.  We share the title with seven other UK Universities.

The aim of the scheme is to promote original research which helps to advance the state of the art: this means both getting such research done in the UK, and developing a pool of expertise for academia, government, and business.  Wise and talented individuals are clearly crucial, and it’s a privilege to work with a large such group in Oxford.

The scheme is modelled after one which has been running in the USA for some time, fronted by the NSA.  Their programme is extensive, and has other components – such as Centres of Excellence in Education, which we might expect to see here in the fullness of time.

Is close association with GCHQ a double-edged sword?  They host the national technical authority for information assurance and so have a good idea of the kind of research which may be useful.  In principle, they also have deep pockets (though not nearly as deep as those of their American counterparts mentioned above).  On the other hand, universities will not stay excellent for very long if they are (or are seen to be) the patsies of the state.  Happily, I think this is recognised by all sides, and we can look forward to some creative tension made possible precisely because our research is “outside the fence”.

There’s an interesting clash of mind-sets to hold in mind, too:  the University is an open and exceptionally international place.  Security research is pursued by people who have not just diverse skills but also a variety of affiliations and loyalties – in contrast to those who work in security for the State, who must generally be citizens or otherwise able to hold an advanced clearance. Having the one inform the other sets up tensions – all the more so if there is to be two-way flow of ideas.  Perhaps an interesting topic of research for those in social sciences would be to ask what a “clearance” might look like in the cyber domain – if not based on citizenship, what might be the baseline for assuming shared objectives?

That is one of many cases which show that the concerns of Cyber Security clearly spread beyond the technical domain in which they first arise. Inter-disciplinary study is essential for the future of this topic.  The next blog post will reproduce an article I recently wrote on the subject.

Do Garfinkel’s design patterns apply to the web?

A widely cited publication in usable security research is Simson L. Garfinkel’s thesis: “Design Principles and Patterns for Computer Systems That Are Simultaneously Secure and Usable”.  In Chapter 10 he describes six principles and about twenty patterns which can be followed in order to align security and usability in system design.

We’ve been referring to these patterns throughout the webinos project when designing the system and security architecture.  However, it’s interesting to note that the web (and web applications) actually directly contradict many of them.  Does this make the web insecure?  Or does it suggest that the patterns and principles are inadequate?  Either way, in this blog post I’m going to explore the relationship between some of these principles and the web.

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Guess again

Over in a fenland blog, there is a little discussion going on about passwords.  Evidently, Google has been doing some advertising about what makes a good password, and this has come in for some criticism.

In that blog post, Joseph Bonneau proposes an alternative one-liner:

A really strong password is one that nobody else has ever used.

(One of the commentors (J. Carlio) suggests modifications to add something about memorability. )

This is a seductive idea: it is, broadly, true.  It encapsulates the idea that you are trying to defeat brute force attacks, and that these generally succeed by attempting plausible passwords.

But I don’t think it’s good advice.    That is mainly because many people are poor with estimates that surround very large numbers: whether the likelihood of my password being used by someone else is one in a thousand, one in a million, one in a trillion (the word of the week, thanks to national debts) is something that, I would say, few people have a good intuition about.  In just the same way, people are poor at risk assessment for unlikely events.

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Aren’t spammers subtle?

Not having managed a blog with such a public profile before, I’m intrigued by the behaviour of those wanting to spam the comments field.

The blog is set up so that individuals from within the group can post using their Oxford credentials. Others can post comments, but the first time they comment, the comment must be moderated.

Some try posting their adverts for herbal remedies right away. Those are easy to spot and throw away.

There are several, though, who have posted comments like “I like this blog. You make good points.” I assume that the aim of these is that they are likely to get approved by a semi-vigilant moderator because then the commenter becomes a trusted poster.  Presumably, the advertising spam would follow thereafter.

I remark on this

  • (a) because other members of the group may moderate comments, and should be on the lookout for this ‘trojan’ behaviour;
  • (b) because it points to a greater degree of tenacity on the part of the spammers than I would have realised existed;
  • (c) because it seems a particularly hard problem to solve, CAPTCHAs notwithstanding.

webinos secure storage: a cross-platform dilemma.

Encrypted storage for sensitive data and credentials is an obvious requirement for any system with pretences towards being secure. As part of the webinos project, we have been thinking about solutions to this problem which work across multiple platforms.

As a brief recap: the webinos project aims to design and deliver an open source web runtime for four types of device: smartphones, media centres, PCs and in-car computers.  It will provide a set of standard JavaScript APIs for accessing device features from web applications, as well as synchronising data and providing a “seamless” end user experience.  We’re working on it with over 20 other companies and are primarily researching the security and privacy aspects of the system.  More details are available on our website: http://www.cs.ox.ac.uk/projects/webinos/

In webinos we think we have (at least) the following data to protect:

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